diff --git a/cache_manager.py b/cache_manager.py
index 5f4f3fa..24c798a 100644
--- a/cache_manager.py
+++ b/cache_manager.py
@@ -243,25 +243,25 @@ class L1CacheManager:
 
     def get_by_content_hash(self, content_hash: str) -> Optional[Path]:
         """Get cached file path by content_hash."""
-        # Check index first
+        # Check index first (new cache structure)
         node_id = self._content_index.get(content_hash)
         if node_id:
             path = self.cache.get(node_id)
-            if path:
+            if path and path.exists():
                 return path
 
-        # Check legacy directory
-        legacy_path = self.legacy_dir / content_hash
-        if legacy_path.exists():
-            return legacy_path
-
-        # Scan cache entries (fallback)
+        # Scan cache entries (fallback for new structure)
         entry = self.cache.find_by_content_hash(content_hash)
-        if entry:
+        if entry and entry.output_path.exists():
             self._content_index[content_hash] = entry.node_id
             self._save_content_index()
             return entry.output_path
 
+        # Check legacy location (files stored directly as CACHE_DIR/{content_hash})
+        legacy_path = self.cache_dir / content_hash
+        if legacy_path.exists() and legacy_path.is_file():
+            return legacy_path
+
         return None
 
     def has_content(self, content_hash: str) -> bool:
diff --git a/server.py b/server.py
index 256a15f..c6a4cd1 100644
--- a/server.py
+++ b/server.py
@@ -161,24 +161,16 @@ def cache_file(source: Path, node_type: str = "output") -> str:
     Copy file to cache using L1CacheManager, return content hash.
 
     Uses artdag's Cache internally for proper tracking.
-    Also creates a symlink in legacy location for backward compatibility.
     """
     cached = cache_manager.put(source, node_type=node_type)
-
-    # Create symlink in legacy location for backward compatibility
-    legacy_path = CACHE_DIR / cached.content_hash
-    if not legacy_path.exists():
-        try:
-            legacy_path.symlink_to(cached.path)
-        except (OSError, FileExistsError):
-            # Symlink failed, try copy
-            import shutil
-            if not legacy_path.exists():
-                shutil.copy2(cached.path, legacy_path)
-
     return cached.content_hash
 
 
+def get_cache_path(content_hash: str) -> Optional[Path]:
+    """Get the path for a cached file by content_hash."""
+    return cache_manager.get_by_content_hash(content_hash)
+
+
 @app.get("/api")
 async def api_info():
     """Server info (JSON)."""
@@ -456,14 +448,14 @@ async def run_detail(run_id: str, request: Request):
 
         # Build media HTML for input/output
         media_html = ""
-        has_input = run.inputs and (CACHE_DIR / run.inputs[0]).exists()
-        has_output = run.status == "completed" and run.output_hash and (CACHE_DIR / run.output_hash).exists()
+        has_input = run.inputs and cache_manager.has_content(run.inputs[0])
+        has_output = run.status == "completed" and run.output_hash and cache_manager.has_content(run.output_hash)
 
         if has_input or has_output:
             media_html = '<div class="grid gap-6 md:grid-cols-2 mb-8">'
             if has_input:
                 input_hash = run.inputs[0]
-                input_media_type = detect_media_type(CACHE_DIR / input_hash)
+                input_media_type = detect_media_type(get_cache_path(input_hash))
                 input_video_src = video_src_for_request(input_hash, request)
                 if input_media_type == "video":
                     input_elem = f'<video src="{input_video_src}" controls muted loop playsinline class="max-w-full max-h-64 rounded-lg"></video>'
@@ -480,7 +472,7 @@ async def run_detail(run_id: str, request: Request):
                 '''
             if has_output:
                 output_hash = run.output_hash
-                output_media_type = detect_media_type(CACHE_DIR / output_hash)
+                output_media_type = detect_media_type(get_cache_path(output_hash))
                 output_video_src = video_src_for_request(output_hash, request)
                 if output_media_type == "video":
                     output_elem = f'<video src="{output_video_src}" controls autoplay muted loop playsinline class="max-w-full max-h-64 rounded-lg"></video>'
@@ -684,14 +676,14 @@ async def list_runs(request: Request, page: int = 1, limit: int = 20):
                 ''')
 
                 # Show input and output thumbnails
-                has_input = run.inputs and (CACHE_DIR / run.inputs[0]).exists()
-                has_output = run.status == "completed" and run.output_hash and (CACHE_DIR / run.output_hash).exists()
+                has_input = run.inputs and cache_manager.has_content(run.inputs[0])
+                has_output = run.status == "completed" and run.output_hash and cache_manager.has_content(run.output_hash)
 
                 if has_input or has_output:
                     html_parts.append('<div class="grid gap-4 sm:grid-cols-2">')
                     if has_input:
                         input_hash = run.inputs[0]
-                        input_media_type = detect_media_type(CACHE_DIR / input_hash)
+                        input_media_type = detect_media_type(get_cache_path(input_hash))
                         html_parts.append(f'''
                         <div class="bg-dark-600 rounded-lg p-3">
                             <div class="text-xs text-gray-400 mb-2">Input</div>
@@ -705,7 +697,7 @@ async def list_runs(request: Request, page: int = 1, limit: int = 20):
 
                     if has_output:
                         output_hash = run.output_hash
-                        output_media_type = detect_media_type(CACHE_DIR / output_hash)
+                        output_media_type = detect_media_type(get_cache_path(output_hash))
                         html_parts.append(f'''
                         <div class="bg-dark-600 rounded-lg p-3">
                             <div class="text-xs text-gray-400 mb-2">Output</div>
@@ -767,38 +759,22 @@ async def list_runs(request: Request, page: int = 1, limit: int = 20):
 @app.get("/cache/{content_hash}")
 async def get_cached(content_hash: str):
     """Get cached content by hash."""
-    # Try cache_manager first (new location)
-    cache_path = cache_manager.get_by_content_hash(content_hash)
-
-    # Fallback to legacy location
+    cache_path = get_cache_path(content_hash)
     if not cache_path:
-        legacy_path = CACHE_DIR / content_hash
-        if legacy_path.exists():
-            cache_path = legacy_path
-
-    if not cache_path or not cache_path.exists():
         raise HTTPException(404, f"Content {content_hash} not in cache")
-
     return FileResponse(cache_path)
 
 
 @app.get("/cache/{content_hash}/mp4")
 async def get_cached_mp4(content_hash: str):
     """Get cached content as MP4 (transcodes MKV on first request, caches result)."""
-    # Try cache_manager first (new location)
-    cache_path = cache_manager.get_by_content_hash(content_hash)
-
-    # Fallback to legacy location
+    cache_path = get_cache_path(content_hash)
     if not cache_path:
-        legacy_path = CACHE_DIR / content_hash
-        if legacy_path.exists():
-            cache_path = legacy_path
-
-    mp4_path = CACHE_DIR / f"{content_hash}.mp4"
-
-    if not cache_path or not cache_path.exists():
         raise HTTPException(404, f"Content {content_hash} not in cache")
 
+    # MP4 transcodes stored alongside original in CACHE_DIR
+    mp4_path = CACHE_DIR / f"{content_hash}.mp4"
+
     # If MP4 already cached, serve it
     if mp4_path.exists():
         return FileResponse(mp4_path, media_type="video/mp4")
@@ -856,8 +832,8 @@ async def cache_detail(content_hash: str, request: Request):
     """View cached content detail. HTML for browsers, JSON for APIs."""
     current_user = get_user_from_cookie(request)
 
-    cache_path = CACHE_DIR / content_hash
-    if not cache_path.exists():
+    cache_path = get_cache_path(content_hash)
+    if not cache_path:
         if wants_html(request):
             content = f'<p class="text-red-400">Content not found: {content_hash}</p>'
             return HTMLResponse(render_page("Not Found", content, current_user, active_tab="cache"), status_code=404)
@@ -1001,8 +977,8 @@ async def ui_cache_meta_form(content_hash: str, request: Request):
     pin_reason = meta.get("pin_reason", "")
 
     # Detect media type for publish
-    cache_path = CACHE_DIR / content_hash
-    media_type = detect_media_type(cache_path) if cache_path.exists() else "unknown"
+    cache_path = get_cache_path(content_hash)
+    media_type = detect_media_type(cache_path) if cache_path else "unknown"
     asset_type = "video" if media_type == "video" else "image"
 
     # Origin radio checked states
@@ -1404,8 +1380,8 @@ async def list_cache(
             html_parts = []
             for item in items_page:
                 content_hash = item["hash"]
-                cache_path = CACHE_DIR / content_hash
-                media_type = detect_media_type(cache_path)
+                cache_path = get_cache_path(content_hash)
+                media_type = detect_media_type(cache_path) if cache_path else "unknown"
 
                 # Format size
                 size = item["size"]
@@ -1509,11 +1485,9 @@ async def discard_cache(content_hash: str, username: str = Depends(get_required_
     - Cannot delete inputs/outputs of activities (runs)
     - Cannot delete pinned items
     """
-    # Check if content exists (in cache_manager or legacy location)
+    # Check if content exists
     if not cache_manager.has_content(content_hash):
-        cache_path = CACHE_DIR / content_hash
-        if not cache_path.exists():
-            raise HTTPException(404, "Content not found")
+        raise HTTPException(404, "Content not found")
 
     # Check ownership
     user_hashes = get_user_cache_hashes(username)
@@ -1535,8 +1509,8 @@ async def discard_cache(content_hash: str, username: str = Depends(get_required_
     success, msg = cache_manager.delete_by_content_hash(content_hash)
     if not success:
         # Fallback to legacy deletion
-        cache_path = CACHE_DIR / content_hash
-        if cache_path.exists():
+        cache_path = get_cache_path(content_hash)
+        if cache_path and cache_path.exists():
             cache_path.unlink()
 
     # Clean up legacy metadata files
@@ -1564,9 +1538,7 @@ async def ui_discard_cache(content_hash: str, request: Request):
 
     # Check if content exists
     if not cache_manager.has_content(content_hash):
-        cache_path = CACHE_DIR / content_hash
-        if not cache_path.exists():
-            return '<div class="bg-red-900/50 border border-red-700 text-red-300 px-4 py-3 rounded-lg mb-4">Content not found</div>'
+        return '<div class="bg-red-900/50 border border-red-700 text-red-300 px-4 py-3 rounded-lg mb-4">Content not found</div>'
 
     # Check if pinned (legacy metadata)
     meta = load_cache_meta(content_hash)
@@ -1583,8 +1555,8 @@ async def ui_discard_cache(content_hash: str, request: Request):
     success, msg = cache_manager.delete_by_content_hash(content_hash)
     if not success:
         # Fallback to legacy deletion
-        cache_path = CACHE_DIR / content_hash
-        if cache_path.exists():
+        cache_path = get_cache_path(content_hash)
+        if cache_path and cache_path.exists():
             cache_path.unlink()
 
     # Clean up legacy metadata files
@@ -1718,15 +1690,9 @@ async def upload_to_cache(file: UploadFile = File(...), username: str = Depends(
         tmp.write(content)
         tmp_path = Path(tmp.name)
 
-    # Hash and move to cache
-    content_hash = file_hash(tmp_path)
-    cache_path = CACHE_DIR / content_hash
-
-    if not cache_path.exists():
-        import shutil
-        shutil.move(str(tmp_path), cache_path)
-    else:
-        tmp_path.unlink()
+    # Store in cache via cache_manager
+    cached = cache_manager.put(tmp_path, node_type="upload", move=True)
+    content_hash = cached.content_hash
 
     # Save uploader metadata
     actor_id = f"@{username}@{L2_DOMAIN}"
@@ -1754,8 +1720,8 @@ class PublishRequest(BaseModel):
 async def get_cache_meta(content_hash: str, username: str = Depends(get_required_user)):
     """Get metadata for a cached file."""
     # Check file exists
-    cache_path = CACHE_DIR / content_hash
-    if not cache_path.exists():
+    cache_path = get_cache_path(content_hash)
+    if not cache_path:
         raise HTTPException(404, "Content not found")
 
     # Check ownership
@@ -1770,8 +1736,8 @@ async def get_cache_meta(content_hash: str, username: str = Depends(get_required
 async def update_cache_meta(content_hash: str, update: CacheMetaUpdate, username: str = Depends(get_required_user)):
     """Update metadata for a cached file."""
     # Check file exists
-    cache_path = CACHE_DIR / content_hash
-    if not cache_path.exists():
+    cache_path = get_cache_path(content_hash)
+    if not cache_path:
         raise HTTPException(404, "Content not found")
 
     # Check ownership
@@ -1819,8 +1785,8 @@ async def publish_cache_to_l2(
     Requires origin to be set in metadata before publishing.
     """
     # Check file exists
-    cache_path = CACHE_DIR / content_hash
-    if not cache_path.exists():
+    cache_path = get_cache_path(content_hash)
+    if not cache_path:
         raise HTTPException(404, "Content not found")
 
     # Check ownership
@@ -1907,8 +1873,8 @@ async def republish_cache_to_l2(
     Only works for already-published items.
     """
     # Check file exists
-    cache_path = CACHE_DIR / content_hash
-    if not cache_path.exists():
+    cache_path = get_cache_path(content_hash)
+    if not cache_path:
         raise HTTPException(404, "Content not found")
 
     # Check ownership
@@ -2547,8 +2513,8 @@ async def ui_runs(request: Request):
         ''')
 
         # Show input and output side by side
-        has_input = run.inputs and (CACHE_DIR / run.inputs[0]).exists()
-        has_output = run.status == "completed" and run.output_hash and (CACHE_DIR / run.output_hash).exists()
+        has_input = run.inputs and cache_manager.has_content(run.inputs[0])
+        has_output = run.status == "completed" and run.output_hash and cache_manager.has_content(run.output_hash)
 
         if has_input or has_output:
             html_parts.append('<div class="grid gap-4 sm:grid-cols-2">')
@@ -2556,7 +2522,7 @@ async def ui_runs(request: Request):
             # Input box
             if has_input:
                 input_hash = run.inputs[0]
-                input_media_type = detect_media_type(CACHE_DIR / input_hash)
+                input_media_type = detect_media_type(get_cache_path(input_hash))
                 html_parts.append(f'''
                 <div class="bg-dark-600 rounded-lg p-3">
                     <div class="text-xs text-gray-400 mb-2">Input: {input_hash[:16]}...</div>
@@ -2572,7 +2538,7 @@ async def ui_runs(request: Request):
             # Output box
             if has_output:
                 output_hash = run.output_hash
-                output_media_type = detect_media_type(CACHE_DIR / output_hash)
+                output_media_type = detect_media_type(get_cache_path(output_hash))
                 html_parts.append(f'''
                 <div class="bg-dark-600 rounded-lg p-3">
                     <div class="text-xs text-gray-400 mb-2">Output: {output_hash[:16]}...</div>
@@ -2666,8 +2632,8 @@ async def ui_cache_list(
 
     for item in cache_items[:50]:  # Limit to 50 items
         content_hash = item["hash"]
-        cache_path = CACHE_DIR / content_hash
-        media_type = detect_media_type(cache_path)
+        cache_path = get_cache_path(content_hash)
+        media_type = detect_media_type(cache_path) if cache_path else "unknown"
 
         # Format size
         size = item["size"]
@@ -2770,15 +2736,15 @@ async def ui_run_partial(run_id: str, request: Request):
     '''
 
     # Show input and output side by side
-    has_input = run.inputs and (CACHE_DIR / run.inputs[0]).exists()
-    has_output = run.status == "completed" and run.output_hash and (CACHE_DIR / run.output_hash).exists()
+    has_input = run.inputs and cache_manager.has_content(run.inputs[0])
+    has_output = run.status == "completed" and run.output_hash and cache_manager.has_content(run.output_hash)
 
     if has_input or has_output:
         html += '<div class="grid gap-4 sm:grid-cols-2">'
 
         if has_input:
             input_hash = run.inputs[0]
-            input_media_type = detect_media_type(CACHE_DIR / input_hash)
+            input_media_type = detect_media_type(get_cache_path(input_hash))
             html += f'''
             <div class="bg-dark-600 rounded-lg p-3">
                 <div class="text-xs text-gray-400 mb-2">Input: {input_hash[:16]}...</div>
@@ -2793,7 +2759,7 @@ async def ui_run_partial(run_id: str, request: Request):
 
         if has_output:
             output_hash = run.output_hash
-            output_media_type = detect_media_type(CACHE_DIR / output_hash)
+            output_media_type = detect_media_type(get_cache_path(output_hash))
             html += f'''
             <div class="bg-dark-600 rounded-lg p-3">
                 <div class="text-xs text-gray-400 mb-2">Output: {output_hash[:16]}...</div>